Abdullah bin Malik narrates from Sayyiduna Uqbah bin Amir (may Allah be pleased with him) that his sister vowed that she would perform Hajj on foot without a head-covering. He said: I mentioned this to the Prophet (peace and blessings be upon him), and he (peace and blessings be upon him) said: "Tell your sister to put on her head-covering, to ride, and to fast for three days."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النذور / 20121